The first paragraph: the overlapping part is a triangle.

At this time, t≥0, when point F moves to CD, t reaches the maximum value, and t≤4/3 is calculated.

S=S(ABC)×(t/6)？ =t？ /4 (use similar)

The second paragraph: the overlapping part is quadrilateral.

At this time, when t≥4/3 and G moves to AC, T takes the maximum value and calculates t≤2.

S=t？ /4-(t-2×2/3)？ ×3/4× 1/2=-t？ 8+2/3

The third paragraph: the overlapping part is pentagonal.

At this time, t≥2, when G moves to CD, T reaches the maximum value, and t≤ 10/3 is calculated.

S=2？ -(2-( 10/3-t))？ ×3/4× 1/2-[(6-2-t)×3/6+(6-t)×3/6]×2× 1/2 =-3/8t？ +2t-5/3

Paragraph 4: The overlapping part is a triangle.

This t≥ 10/3 is obviously ≤4.

S = ... (Calculate the similarity yourself and give you a chance) ... =-t/2+5/2.

hum ................................