Trust vs. "rely on"

[Ann]

Common Errors in English, Advanced Level

ESL/EFL Test #10 "Late at the Office", question 1

Mary could always be trusted on to be late for work.

(a) could
(b) trusted on
(c) be
(d) for work

Common Errors in English, Advanced Level

ESL/EFL Test #10 "Late at the Office", answer 1

Mary could always be relied on to be late for work.

Correct entry: relied on
The error was: (b) trusted on
_________________________

Hello,

Can you explain what difference between "trust" and "rely"?

Btw, what does this sentence mean?
Why "Mary could always be trusted on to be late for work"?

Thank you very much.

Ann

[Alan]

Hi Ann,

You asked: