From Longman Dictionary of Contemporary Englishbe in the middle of (doing) somethingbe in the middle of (doing) somethingBUSY/NOT AVAILABLEto be busy doing something Can I call you back – I’m in the middle of a meeting. I was in the middle of sorting some papers when the phone rang. → middle
Examples from the Corpus
be in the middle of (doing) something• He's in the middle of a meeting.• I'm in the middle of fixing dinner -- can I call you back?• Todd Dexter was in the middle of the Tet Offensive near Saigon and had little time to appreciate his surroundings.• The grunts were in the middle of a fire mission.• The kid who still enrolled at the school where he was in the middle of all that trouble.• I listened to others' crises but didn't want to accept that I was in the middle of my own.• It was in the middle of the miners' strike, and feelings were running high.• Mr Malik was in the middle of a group crowded round Mafouz.• We were in the middle of that when he was called inside to do his homework and I was sent home.• The Z42 is in the middle of the field on print speed.