. The boy was sitting at the desk, ______ hard when his mother got home.
| A．to pretend to work | B．to pretend to be working |
| C．pretending to work | D．pretending to be working |
We should consider the students’ request the school library provide more books on popular science.
| A．that | B．when | C．which | D．where |
—Is there any possibility you could pick me up at the airport ?
—No problem
| A．when | B．that | C．whether | D．what |
The how to book can be of help to wants to do the job.
| A．who | B．whomever | C．no matter who | D．whoever |
The fact has worried many scientists ______ the earth is becoming warmer and warmer these years.
| A．what | B．which | C．that | D．though |
She is very dear to us. We have been prepared to do it takes to save her life.
| A．whichever | B．however | C．whatever | D．whoever |