My bicycle is nowhere to be found. Who ___ have been using it?

I lunchwhen I learned that former British prime minister Margaret Thatcher had passedaway

100. My cousin wants to be a scientist and _____ science of nuclear.

Is there anything I can do for you?—There seems to have been a technical problem—______，that’s what they told me

the trainer was sure that the whale could look after itself, he _______ it into the sea.