听力文本如下：

Shawn says that Vision Corporation is alarmed by these changes in the market share.

To be “alarmed” (alarmed) means to be shocked, disturbed, or surprised in a negative way.

You might be alarmed to learn that your friend's car was stolen, for example - you are shocked; you are surprised; it's a bad thing.

Shawn says that the company wants to understand the underlying reasons for the changes in market share.

An “underlying (underlying) reason” is an explanation that cannot be seen easily - that you can't figure out right away - but it's an explanation that tells you why something is happening.

An underlying reason for the increase in global temperatures - in global warming - might be the use of oil (petroleum).

That's an example of an “underlying reason.”

Shawn doesn't know exactly what the underlying reason is for the company losing market share, but he talks about three things that may “contribute to the cause”.

“To contribute” (contribute) means to add to something or to make something stronger or better.

If you give money to an organization, you are contributing to the organization.

A “cause” (cause) is something that creates a change or results in something else happening.

Bad weather might be the cause of an accident; it's the reason why the accident happened.

When Shawn talks about three things that “contribute to the cause,” he means that he has identified three things that are part of the situation that is making the company lose its market share.

Shawn says that the first thing is “a growing number of competitors.”

When we say a number is “growing,” we mean it is increasing, so there is an increasing number of competitors.