真(っ) + i-Adjective-stem/Noun

Usage

Very; pure; totally; right; mid-

真っ赤な夕日が海に沈んでいく。 The evening sun is set to set in the ocean.

橋の上から真下にある川を見ると、とても怖い。 Looking at the river directly below from the top of the bridge is very scary.