Tina usually spends time ______ her parents ______ weekends.
| A．in; on | B．with; on |
| C．in; with | D．with; with |
It was not very warm ______ the sun came out.
| A．although | B．because |
| C．so | D．but |
The number 6,743,234,123 is read ____ .
| A．Six billion, seven hundred and forty-three million, two hundred and thirty- four thousand, one hundred and twenty-three |
| B．Six billion and seven hundred and forty-three million and two hundred and thirty four thousand and one hundred twenty-three |
| C．Six billion and seven hundred and forty-three million and two hundred and thirty four thousand and a hundred and twenty-three |
| D．Six billions, seven hundreds and forty-three millions , two hundreds and thirty -four thousands a hundred and twenty-three |
I ____ my clothes when my father got home.
| A．wash | B．washed |
| C．am washing | D．was washing |
We should protect the earth because it's home to ____ animals.
| A．million | B．millions |
| C．million of | D．millions of |