Вот правильные ответы на ваши предложения с глаголами в инфинитиве или форме -ing:
1)
a) John will never forget planting his first tree. (plant)
b) Don't forget to plant the vegetables this afternoon. (plant)
2)
a) Kate meant to leave for the conservation day earlier, but something came up. (leave)
b) If you want to be at the park by 8:00 am, that will mean leaving the house at around 7:00. (leave)
3)
a) After clearing footpaths for 3 hours, Anne stopped to take a break. (take)
b) You should stop taking things so seriously all the time! (take)
4)
a) I remember meeting that man before, but I can't remember his name. (meet)
b) Remember to meet us outside the homeless shelter at 8:00 pm. (meet)
5)
a) Rosa is trying to reduce air pollution by not driving to school. (reduce)
b) Why don't you try reducing the amount of rubbish you throw away? (reduce)
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