a) I write every day.
I'm writing now.
I was writing at this time yesterday.
I have just written.
I wrote yesterday.
I'll write tomorrow.
b) I have just played.
I'll play tomorrow afternoon.
I played yesterday afternoon.
I play every afternoon.
I'm playing right now.
I was playing when mother came home.
c) I have just drunk milk.
I'll drink milk tomorrow afternoon.
I drank milk yesterday afternoon.
I drink milk every afternoon.
I'm drinking milk right now.
I was drinking milk when mother came home.
d) I'm singing now.
I'll sing tomorrow.
I was singing when father called me.
I have just sung.
I sing every day.
I sang yesterday.
