One of the most important questions they had to consider was _______ of public health.
| A．what | B．this | C．that | D．which |
I'm sorry you've been waiting so long，but it'll still be some time ________ Brian
gets back.
| A．before | B．since | C．till | D．after |
His mother likes to have him next to her ________ she can keep an eye on him.
| A．where | B．in which | C．there | D．when |
—You should have thanked the hostess before leaving.
—I meant ________.But I couldn't find her when I was leaving.
| A．to do | B．to | C．doing | D．doing so |
________ change your mind, do let me know.
| A．If should you | B．Should if you |
| C．Should you | D．You should |
In ________ most countries, a university degree can give you ________ flying start in life.
| A．the; a | B．the; 不填 |
| C．不填；不填 | D．不填；a |