Rearrange the sentences using the following words: has/ She/ a/ face./ round

Rearrange the sentences using the following words.
1. has / She / a / face. / round /
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2. by / we / Shall / bicycle / go / ?
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3.with / a lot of / The air / smoke / in the area / is / polluted / from factories./
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4. is / The Mekong / the / river / in Viet Nam ./ longest /
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5.We / help / old people. / should /
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