The crossing was blocked by many trucks and buses, made it impossible for us to go to work on time.
While we are developing agriculture and industry, we must prevent the earth ______.
When _______ help, one often says “Thank you.” or “It is kind of you “
Frank insisted that he was not asleep______ I had great difficulty in waking him up.
_______seems to have been a strong competition in China for school leavers to enter college or university.
It is these poisonous products ______can cause the symptom of the flu, such as the headache and aching muscles.