If two triangles are congruent, then the six
a0parts are congruent.

If two triangles are congruent, then the six corresponding parts are congruent

Explanation:
When writing congruency, the order of writing the letters is extremely important. This is because each side/angle in the first triangle would be congruent to its corresponding side/angle in the other triangle.

Example:
If triangle ABC is congruent to triangle DEF, then:
angle A = angle D
angle B = angle E
angle C = angle F
AB = DE
BC = EF
AC = DF

Hope this helps :)