We must do the experiment carefully__________Miss Liu told us.
| A．what | B．since | C．as | D．while |
______ when we passed by its nest.
| A．Up into the blue sky did the bird fly | B．Up into the blue sky flew the bird |
| C．Up into the blue sky the bird flew | D．Flew up into the blue sky the bird |
“Sorry” is the hardest word to say sometimes. _______ you know you’ve done something wrong, or something inappropriate, it takes courage to say sorry.
| A．Only if | B．Even if | C．If only | D．As if |
______ for the breakdown of the school computer network, Alice was in low spirits.
| A．Blaming | B．Blamed | C．To blame | D．To be blamed |
With more and more forests disappearing, today the public is much concerned about the way _________.
| A．nature is being ruined | B．which nature is ruined |
| C．on which to ruin nature | D．of nature to be ruined |
Without the friction (摩擦力) between feet and the ground, people would ______ be able to walk.
| A．in no time | B．by all means | C．on any account | D．in no way |