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Answer:
The G is silent (but may affect pronunciation) in these types of words:

-IGH words : high, sigh, sleigh, weigh

-IGHT words : flight, light, height, weight

-IGN words : benign, design, feign, reign, sign, campaign, foreign

-IGM and -AGM words : paradigm, diaphragm

-OUGH words: bough, though, rough, tough

-OUGHT words : bought, brought, fought, thought, wrought

-AUGHT words : caught, naughty, taught

GN- words : gnat, gnaw, gnome, gnomon