1. Can we start refuelling the plane? Yes, I'd say this is written correctly. 2 Is there anybody left on the board plane. No, the correct question would be - 'Is there anybody left on board the plane?' 3 The teacher got the pupils in the class and started lesson. No, a correction could be - 'The teacher got the pupils into the class and started the lesson'. 4 I went to a dentist to cure my ill tooth. No, it doesn't sound right. 'I went to a dentist to cure my bad tooth' sounds more natural.

I disagree with Allan ChesterEnglish’s correction of 4. In my opinion you don’t cure a bad tooth, you treat it. And since it’s the dentist who treats the bad tooth and not the “I” you don’t say “I went to a dentist to treat my bad tooth”, but “I went to a dentist to have my bad tooth treated” More informally you could also say: “I went to a dentist to have my bad tooth fixed”