How many __(bus)__(driver)__(be)there in the picture?后面的回答：there __(be)one.

How many __(bus)__(driver)__(be)there in the picture?后面的回答：there __(be)one.
How many __(bus)__(driver)__(be)there in the picture?后面的回答：there __(be)one.

How many __(bus)__(driver)__(be)there in the picture?后面的回答：there __(be)one.
How many bus (bus)drivers (driver)are (be)there in the picture?后面的回答：there is (be)one.

bus drivers（固定搭配 公共汽车司机） are （many提问用复数）
is(一个是单数)