what

I think about what to prepare.

私は何を準備するか考えます

I think about what to prepare tomorrow.

私は明日何を準備するか考えます

I think about what to prepare in the meeting room tomorrow.

私は明日会議室で何を準備するか考えます

I think about what to prepare in the meeting room with my coworkers tomorrow.

私は明日会議室で同僚たちと何を準備するか考えます

I think about what to prepare for the presentation in the meeting room with my coworkers tomorrow.

私は明日会議室で同僚たちと発表のために何を準備するか考えます