Learn Turkish: Sapsarı güneş bizi ısıtıyordu. - The bright yellow sun was warming us.

To intensify adjectives like sarı, you take the first syllable (sa), add a specific consonant (m, p, r, or s), and then attach the whole original word. For sarı, the chosen consonant is p, giving us sa + p + sarı = sapsarı. Which consonant to use isn't based on a strict rule, so you just have to memorize it for each adjective.

Why does this sentence use bizi instead of just biz?

Biz means "we" or "us." Here it takes the accusative case ending -i because "us" is the specific direct object receiving the action of the verb ısıtıyordu (was warming). Since the sun is warming us, biz becomes bizi.

What suffixes are attached to the verb ısıtıyordu to mean "was warming"?

It breaks down into the verb stem ısıt- (to warm/heat), the present continuous suffix -ıyor (is warming), and the past tense suffix -du (was). Combined, -ıyordu creates the past continuous tense, showing that an action was ongoing in the past.

Is the verb stem ısıt- related to the word ısı (heat)?