sb cannot think of anythink to say

He stood up on stage to compete, and, of course,
his mind went blank!  Google

As he was about to activate the warp drive, his mind went blank;
his unconscious body slumped inside the ship’s capsule. Google

He felt like he was to blame for his father’s
death and his mind went blank.  google

not remember at all

I've actually had mornings where I've been reduced to tears simply because I can't
for the life of me remember where I put a blouse or pair of shoes. Google

It's funny but last year I fought and fought having a committed relationship
and now that I'm in one I can't for the life of me remember why. Google

I remember that perfectly, although I can't
for the life of me remember his name.  Google

if sth slips your mind, you forget about it

This just slipped my mind, but it's back now.... Call it a senior moment,
but he has a very valid point. Google

I forgot to phone you last night. I'm sorry. It slipped my mind. google

I forgot to phone you last night. I'm sorry. It slipped my mind. Gogle

be very good at remembering things

The new teacher has a memory like an elephant.  Google

I attribute his problems to be because he
has a memory like an elephant. Google

 Isabella has a memory like an elephant. She forgets nothing.
 Google

stupid jokes that are rude but not offensive

One thing that always annoys me is that people refer to this kind
of thing as "schoolboy humour" as if that's an automatic slant. Google

As was pointed out earlier, this is schoolboy humour, and I don't know why he bothers
because the truth is that he is vegetarian-friendly. Google

With his schoolboy humour and distinctive,
cheerful voice, "Johnners" was a friend to millions of radio listeners.  Google

be physically very strong but not very intelligent

There is a perception that Domi is all brawn and no brains but that is the furthest thing from the truth. Google

He is all brawn and no brains but don't telll him that to his face, cause he might feed you a knuckle sandwitch.  Google

Someone who is all brawn and no brains....Fred Flintstone would fill that role for us for a solid 10 years. Google

be very stupid

He is dead from the neck up; a thick,
jarhead tough-guy with no more personality than a bag of bricks. Google

Egalitarianism as a philosophy is dead from the neck up, insofar as
even its adherents do not and, indeed, cannot take it seriously.  Google

This project is dead from the neck up. google

be stupid

Every time he opens his mouth,
he confirms our worst fears that he has nothing between his ears. Google

Dan has NOTHING between his ears
worth noting . Google

We have a runt as a Prime Minister, who has nothing between his ears, and we have
no armed services because our government has run them into the ground. Google

know about a lot about sth which most people do not know about

With skills to match their perseverance it’s only a matter of time before the
overground is in the know and flexing their fingers by pressing ‘play. Google

Everyone who is in the "know" knows their NASCAR. Google

Dan is the man who is in the know about birds of prey. Google

know a lot about a particular subject

It is a labour of love, written by a man who knows
his Alps and knows his onions ! Google

So there you go, take some advice
from a man who certainly knows his onions. Google

Any investment broker who knows his
onions will have something nice to say about that!  Google

a person or a book with a lot of information

This book is a mine of information, but it is no dry history book, nor
a guide for geologists and miners. Google

The ECATT site is a mine of information on all aspects of the digital economy,
including materials, links and cases related to flexible working !  Google

This book is a mine of information on all aspects of gold and its uses. Google

sb who is always trying to seem more clever than everybody else in a way that is annoying

Never respond with a smart-aleck remark in return. Google

At every opportunity, simply show you're not affected, and never stoop to being a smart aleck yourself. Google

Lisa Remer Carla's music shows that being a smart aleck isn't necessarily a bad thing.  Google

be the person who organizes sth, esp. sth successful

The Prosecution had long claimed that Federman
was the "brains" behind the Bat Ayin plot. Google

Bob McTavish was the brains behind the shortboard revolution
coming out of Australia in the late 60s.  Google

There, he was the brains behind the building of the Colossus code-breaking
computer which was used to decipher enemy messages. Google

an intelligent person

Little do they realise what a bright spark he must have been in his youth. Google

Be a bright spark – use electricity safely. Google

 Then, one day a bright spark will discover how to make a bright spark, and
the whole bloody saga will begin again...  Google

to be very intelligent and able to think quickly

Neil Turner is as bright as a button and as sharp as a blade. Google

He is not yet fully house-trained but is as
bright as a button and quick to learn. He is a normal mischievous puppy.  Google

He is as bright as a button,
and has a gift of bringing a smile to the hardest of faces. Google