1. Twenty years is a long time.
2. twenty years is a long period.
3. 100 kg is very heavy.
4. 100 kg is a heavy weight.
5. Two hundred dollars is a lot of money for me.
6. Two hundred dollars is a great/good sum of money.
7. Twenty miles is a long distance.
8. Twenty miles is very long.
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Would you check the sentences? Correct errors, please?
They are all correct.
The sentences appear to be grammatically correct, but there are a few suggestions that can make them more concise and natural. Please find the revised sentences below:
1. Twenty years is a long time.
2. Twenty years is a lengthy period.
3. 100 kg is very heavy.
4. 100 kg is a significant weight.
5. Two hundred dollars is a lot of money for me.
6. Two hundred dollars is a substantial/generous amount of money.
7. Twenty miles is a long distance.
8. Twenty miles is a considerable distance.