Are these sentences correct?
My sweater shrank when it was washed.
It may be shrink if you wash it at a very high temperature. (wearing apparel)
My savings quickly shrank because I've haven't worked for a long time.
My savings quickly shrank because I've been out of business for a long time.

Question

Are these sentences correct?
My sweater shrank when it was washed.
It may be shrink if you wash it at a very high temperature.   (wearing apparel)
My savings quickly shrank because I've haven't worked for a long time.
My savings quickly shrank because I've been out of business for a long time.

Answer

My sweater shrank when it was washed. - Correct
It may shrink if you wash it at a very high temperature. / It might become shrunken if you wash it at a very high temperature.
My savings quickly shrank because I hadn't worked for a long time. (you mixed past with present perfect)
My savings quickly shrank because I had been out of business for a long time.

Answer

My sweater shrank when it was washed.-correct
It may be shrink if you wash it at a very high temperature. (wearing apparel) 
It may shrink if you wash it at a very high temperature.
My savings quickly shrank because I've haven't worked for a long time. 
My savings quickly shrank because I haven't worked for a long time.
My savings quickly shrank because I've been out of business for a long time.-correct

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