Very often in IELTS Writing and Speaking, candidates would like to express the idea of ‘necessity’. It is possible to use ‘have to’. Here are some alternatives:
It is absolutely imperative that governments take steps to alleviate poverty.
It is essential/vital that those in power take the issue of poverty seriously.
The authorities simply must address the issues of poverty and inequality without delay.
It is the duty of political leaders to tackle the problem of social inequality.
I believe that our leaders have a clear obligation to ensure that nobody remains below the poverty line.
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