I am so tired，for I ________ English for 2 hours.
| A．is studying | B．have been studying |
| C．was studying | D．had been studying |
John Wood，an Internet blogger，discovered that Samsung ________ for not protecting its workers from a dangerous chemical used on its phones.
| A．had criticized | B．had been criticized |
| C．was criticized | D．was criticizing |
My mind wasn't on what he was saying，so I'm afraid I ________ half of it.
| A．was missing | B．had missed |
| C．will miss | D．missed |
All the preparations for the task ________，and we're ready to start.
| A．completed | B．complete |
| C．had been completed | D．have been completed |
Selecting a mobile phone for personal use is not an easy task because technology ________ so rapidly.
| A．is changing | B．has changed |
| C．will have changed | D．will change |
Visitors ________ not to touch the exhibits.
| A．will request | B．are requested |
| C．are requesting | D．request |
—Sorry，sir，your car isn't ready yet.
It ________ by our workers.
—Oh，my God，when can I come to fetch it?
| A．is repaired | B．has been repaired |
| C．is being repaired | D．will be repaired |
If their marketing plans succeed，they ________ their sales by 20 percent.
| A．will increase | B．have been increasing |
| C．have increased | D．would be increasing |
The wet weather will continue tomorrow when a cold front ________ to arrive.
| A．is expected | B．is expecting |
| C．expects | D．will be expected |
We first met on a train in 2010，but we both felt immediately that we ________ each other for years.
| A．knew | B．have known |
| C．had known | D．know |