Place a towel over your head to keep the steam in and heighten the effect.
The Sun
They certainly don't heighten the effect.
The Times Literary Supplement
On most occasions, he would slightly speed up the reactions to heighten the effect.
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Highlighted cheeks and wrinkles heighten the effect of sadness and helplessness, which directly emanate from the character.
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Some are made of sateen fabrics, which further heighten the effect of the quilting.
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