When we want to use the そうです construction with verbs, we have to use the verb
stem:

> 雨が **降り** そうです。

Is it possible to express the past with そうです? (it looks like it has
rained/rained)

Or is it only correct to use みたいです for the purpose:`雨が降ったみたいです`？
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2019-02-15T05:56:53.247
65506
2019-02-15T14:48:45.177
31549
question
grammar
Verb + そうです　to express the past
It is possible to express the past with 「そうです」.  
「昨日雨が降ったそうです」 roughly translates to 'I heard it rained yesterday'. Just to be
clear, 「そうです」 doesn't have any meaning of 'hearing'. 「そうです」 expresses that you
have not directly observed the rain, so you're not 100% sure whether it
happened, but know the information from other indirect means.  
Since I don't have the ability to add to the comments, I'll add a few more
things from the comments here.  
「降りそう」-> 'It seems it might rain'  
「降るそう」-> 'Heard it's going to rain'  
Both are rough translation to get the feel of uncertainty of the word 「〜そう〜」
has.
CC BY-SA 4.0
2019-02-15T06:40:32.750
65507
2019-02-15T14:48:45.177
2019-02-15T14:48:45.177
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answer