Chọn đáp án đúng ở thì Hiện tại đơn

Chọn đáp án đúng ở thì Hiện tại đơn:
They usually ……………… in the early morning. *
sing
sings
singes
singing
They ………………(plant) trees every early year. *
plants
plant
plantes
are planting
Kathy usually ______ in front of the window during the class. *
sits
sitting
sit
is sit
My mother sometimes …………………(do) morning exercises at 5.30. *
do
does
doing
are
He ______ share anything to me *
don’t do
isn’t
not
doesn't