David, _____ I have been sharing a dorm for more than two years, is quite a funny guy.

The reason ______ Tom came to attend the meeting was ______ he was an expert in this field.

---What do you think of the film?
---Cool! Never before _____ a better one.

Generally speaking, if ______ strictly following the instructions, the electric bike is not as dangerous as reported.

On the National Day, up _____ into the air. Then the crowed cheered.

Before a problem can be solved，it must be obvious____the problem itself is.

We’ve offered her the job, but I don’t know______ she’ll accept it.

After five hours’ drive, they reached       they thought was the place they’d been dreaming of.
Athat           Bwhere          Cwhich              Dwhat

I don’t know_____the future holds in store for me，but I’ll face the storms of life bravely.

It was never clear _______ the man hadn’t reported the accident sooner.