We always go shopping on / in / at the weekend. 2 let’s meet on / in / at 8.30. 3 i’ll give you a call on / in / at two weeks’ time. 4 what would you like to do at / in / on the morning? 5 they started the course on / at / in january. 6 in / on / at christmas day we often go for a walk. 7 do you eat special food on / at / in christmas? 8 what did he do in / at / on friday? 9 i went to university in / at /on the 1990s. 10 rebecca bought a car at / on / in july.