Meaning: He was scared and unsure of what he would find.
Choice of Words: His hands shook as he stretched them out. "Trembling" means shaking slightly and uncontrollably. "Reached out" means extended his hands towards something.
Alternative Expressions
With trembling hands, she reached out to comfort her crying child.
Meaning: This sentence describes a person who is using their trembling hands to try to make their crying child feel better.
Choice of Words: Here, with shows that the trembling hands are connected to the action of reaching out. Comfort means to make someone feel better when they are upset. Crying describes a child who is shedding tears.