pliss tolong dijawab ya

1.
(+) the teacher is informing about the speaking contest
(-) the teacher isn't informing about the speaking contest
(?) Is the teacher informing about the speaking contest?

2.
(+) the farmer is cultivating his rice field
(-) the farmer isn't cultivating his rice field
(?) is the farmer cultivating his rice field?

3.
(+) the students are having an experiment in the field
(-) the students aren't having an experiment in the field
(?) are the students having an experiment in the field?