________ the safety of gas, the government has checked the city’s gas supply system thoroughly．

To ensure

Ensuring

Having ensured

To have ensured

Rainforests ________ and burned at such a speed that they will disappear from the earth in the near future．

cut

are cut

are being cut

had been cut

I couldn’t do my homework with all that noise ________．

going on

goes on

went on

to go on

Although the causes of cancer, we do not yet have any practical way to prevent it．

are being uncovered

have been uncovering

are uncovering

have uncovered

My friend Martin was very sick with a strange fever; ________, he could neither eat nor sleep．

as a result

after all

any way

otherwise

I have to go to work by taxi because my car ________ at the garage．

will be repaired

is repaired

is being repaired

has been repaired

At the beginning of class, the noise of desks ________ could be heard outside the classroom．

opened and closed

to be opened and closed

being opened and closed

to open and close

He went away, ________, and all the valuable things were stolen．

leaving the door be opened

with the door left open

with the door leaving open

left the door being open

We’re going to ________ with some friends for a picnic．Would you like ________?

get in; join us

get over; to join us

get along; to join in us

get together; to join us

I fell asleep while reading the English textbook．Luckily, my roommate ________ time．

wake me up on

woke me up in

wake up me on

woke up me in