1) I knew it would be a shower today but not like cats and dogs--what does this means.
A shower indicates a light rain or a soft rain. To rain like cats and dogs indicates a very heavy rain, a deluge, a drenching rain or downpour.
2) Also is this correct-I was in shower when you called me or it should be
"I was in a shower when you called me.
I was in the shower when you called me.
I was taking a shower when you called me.
3) I take shower every day. Do say just shower or "a shower
I take a shower everyday.
I shower everyday.
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