He tried to deal with the ever-increasing burden of his work,but finally _____ and had to take a complete rest.
He’s rather walk than ___ a bus in the rush hour.
I’m quite familiar ___ the writer who wrote these songs.
We made plans for a visit but _____ difficulties with the car prevented it.
He didn't _____ what I read because his mind was on something else.
Scientists have to work hard to keep _____ with modern discoveries and developments.