. ________ he realized it was too late to return home.
| A．Not until dark | B．It was until dark |
| C．It was not until dark that | D．It was dark that |
Tom’s mother always told him not to smoke again, but _____ didn’t help.
| A．he | B．it |
| C．which | D．as |
.Was it through Mary , ____ was working at a high school , _____ you get to know Tom ?
| A．who, who | B．that, which | C．who, that | D．who, which |
“Where is Mother.” “She is in the kitchen. She _______ the housework all morning.”
| A．is doing | B．was doing |
| C．has done | D．has been doing |
“Was Andrew there when you arrived?” “Yes, but he ______ home soon afterwards.”
| A．had gone | B．has gone |
| C．is going | D．went |
Please call again. Jim _______ a bath just now.
| A．has had | B．was having |
| C．is having | D．has |