27. In the absence ____ necessary exercise, he can get ill easily. So he is often absent ___ class.
| A．for / in | B．of / for | C．of / from | D．with / from |
In _________eyes of children, playing on the Internet can only bring them ________great fun.
| A．the；a | B．不填；a |
| C．the；不填 | D．不填；不填 |
The keeper of the spring cleared away the leaves and branches, and wiped away the silt(淤泥) that would _______ have choked and polluted the fresh flow of water.
| A．thus | B．otherwise |
| C．therefore | D．later |
Most students are for the new school rule, which says all the students not take their cell phones into the classroom.
| A．will | B．can | C．shall | D．must |
He was admitted to our school two years ago, a top school in our hometown, _____ he has been crazy about reading electronic novels, killing time.
| A．after that | B．since that |
| C．after when | D．since when |
The young couple, who returned my wallet, left _____ I could ask for their names.
| A．before | B．while | C．after | D．since |