1) He ________ (has improved / improved) never her knowledge of French cuisine. 2) She ________ (has taken / took) part in studying the problem last week. 3) Where ________ (has worked / did work) he as a volunteer? 4) I ________ (haven't seen / didn't see) her since the last holiday. 5) The volunteers ________ (have cleaned / cleaned) the city three days ago. 6) The money from the company ________ (hasn't come / didn't come) since last spring. 7) We ________ (has seen / saw) the terrible accident ten days ago. 8) They ________ (have missed / missed) the brilliant opportunity to win the competition. 9) We ________ (have moved / moved) to the country since spring. 10) They ________ (have brought / brought) already all the necessary information to broaden the students' horizons of the etiquette.