1). complete the phrasal verbs with the correct particle: .

1. it’s hard for elderly people to keep changes in computer technology.

2. he approached me and growled: ” keep from my daughter! ”

3.though robin was constantly chased by the sheriff, he kept helping the poor.

4. i had a feeling she was keeping something important .

5. it’s too late! keep the radio

2). fill in the gaps with the correct preposition

1. the requirements the contest were extremely strict.

2. the teenagers were charged vandalism.

3.who was responsible the organizing the party? it was a real failure!

4.smoking in public places is the rule.

5.clients were tricked believing their money had been invested.

Sure! I will gladly help you with the questions. Let's start with the first set of questions, which involves completing the phrasal verbs with the correct particle.

1. it’s hard for elderly people to keep up with changes in computer technology.
Explanation: The phrasal verb "keep up with" means to stay informed or updated on something. In this sentence, it means that elderly people find it difficult to stay informed about the changes in computer technology.

2. He approached me and growled: "keep away from my daughter!"
Explanation: The correct particle for the phrasal verb "keep away" is "from." It means to maintain a distance or avoid something. In this context, the person is warning someone to stay away from his daughter.

3. Though Robin was constantly chased by the sheriff, he kept on helping the poor.
Explanation: The correct particle for the phrasal verb "keep on" is "on." It means to continue doing something. In this sentence, despite being chased by the sheriff, Robin continues to help the poor.

4. I had a feeling she was keeping something important from me.
Explanation: The correct particle for the phrasal verb "keep from" is "from." It means to hide or withhold something. In this sentence, the speaker suspects that the woman is not telling him something important.

5. It's too late! Keep the radio on.
Explanation: The correct particle for the phrasal verb "keep on" is "on." It means to not turn off or continue having something in a certain state. In this context, the instruction is to keep the radio turned on because it is too late to change the situation.

Now, let's move on to the second set of questions, which involves filling in the gaps with the correct prepositions.

1. The requirements for the contest were extremely strict.
Explanation: The correct preposition to indicate the relationship between "requirements" and "contest" is "for." It shows that the requirements are specifically related to the contest.

2. The teenagers were charged with vandalism.
Explanation: The correct preposition to show the accusation or attribution of an action is "with." In this sentence, the teenagers are being accused of committing vandalism.

3. Who was responsible for organizing the party? It was a real failure!
Explanation: The correct preposition to show the relationship between "responsible" and "organizing" is "for." It indicates that someone was in charge of organizing the party.

4. Smoking in public places is against the rule.
Explanation: The correct preposition to denote opposition or violation is "against." It shows that smoking in public places is not allowed according to the rule.

5. Clients were tricked into believing their money had been invested.
Explanation: The correct preposition to indicate deception or manipulation is "into." It shows that the clients were misled or convinced to believe something false.

I hope this explanation and step-by-step solution help clarify the answers for you. If you have any further questions, feel free to ask!