Do both of the following sentences have the same meaning?
1- My salary is twice higher than yours.
2- My salary is twice as high as yours.
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In standard English you are more likely to hear the second sentence than the first. Technically, the two sentences mean different things.
My salary is twice higher than yours.
This means I get paid three times your salary.
My salary is twice as high as yours.
This means I get paid two times your salary.
In reality, if I heard the first sentence, I would not be sure if the person was trying to say that they earned twice as much as me (but got the maths wrong) or three times as much as me (and got the maths right).