fell flat on his face

[user_gary]

All the boys had lined up with full of hope of winning the race and making their fathers proud. There was one boy in particular, who was running near the lead and thought of making his father proud. As he speeded down the field across a shallow, he lost his step and slipped. Even though he tried to balance himself he fell flat on his face. He felt very embarrassed and wished to disappear. But, his father stood up and showed his anxious which clearly asked him to get up and win the race.

Could anyone explain the highlighted words?

[Anglika]

All the boys had lined up with full of hope of winning the race and making their fathers proud. There was one boy in particular, who was running near the lead and thought of making his father proud. As he speeded down the field across a shallow, he lost his step and slipped. Even though he tried to balance himself he fell flat on his face. He felt very embarrassed and wished to disappear. But his father stood up and showed his anxious [again there is something missing here - or do you mean to say "his anxiety] which clearly asked him [confusing - better to say "his son"] to get up and win the race.

Could anyone explain the highlighted words?

(1) near to the leading runner

(2) [Is there a word missing? Shallow what =- dip, stream, hole?] as he ran quickly down the field, across the shallow whatever it is

(3) he fell at full length on the ground with his face downwards.

[user_gary]

(1) near to the leading runner

(2) [Is there a word missing? Shallow what =- dip, stream, hole?] as he ran quickly down the field, across the shallow whatever it is

Thank you.

It is shallow hole. (Please again explain this line. I could not understand it)
Also,
leading runner mean (runner on first place?)

[angliholic]

Thank you.

It is shallow hole. (Please again explain this line. I could not understand it)
Also,
leading runner mean (runner on first place?)

A shallow hole is not a deep hole.

A leading runner is the one who runs the fastest/leads the rest of other runners.

[Anglika]

As he speeded down the field, across a shallow hole, he lost his step and slipped.

As he ran quickly down the field, his foot was caught in a shallow hole and he tripped.