Something that ushers in another thing indicates that the other thing is about to begin.
Example: The arrival of Europeans in Asutralia ushered in a new era for the Aborigines.
introduces
Example: The government will bring in a new law to stop the problem.
For more meanings of the phrasal verb bring in, follow the link.
more information: bring in
We usually say wards off instead of wards away. Both ward off and ward away mean to prevent or stop.
When too means 'more than' it's spelled with 2 o's. Follow the link for more.
more information: to too
To take part is to join in or become part of a group doing something.
Example: She's taking part in the school play.
Click here for more idioms and common expressions.
Have been parading is the present perfect continuous tense, used to talk about an action that has begun in the past that is still continuing. Follow the link to find out more.
more information: present perfect continuous tense
Usually we say that someone is 78 years old or 5 years old as the case may be. But here he wants to make the point that he feels young and so deliberately doesn't use the conventional 'old' after his age.
Well, I am 78 years young
Here taught is the past tense of the irregular verb teach. Follow the link below to find out more and to listen to some examples.
more information: teach
concentate on what you are doing
Example: You have to keep you mind on the job when you're driving in heavy traffic.