It's useful to be able to quote Pew Research on subjects such as my title above.  That's because, unlike the Center for Immigration Studies [CIS], Pew hasn't been honored as a "hate group" by the moral cretins at the Southern Poverty Law Center [SPLC—or $PLC, here at VDARE.com], and this distinction is important to lazy journalists (most of whom are also immigration ignoramuses).

So, for example, in May 2013 Steve Camarota and Karen Ziegler of CIS reported, based upon U.S. Census Bureau data for 2009 - 2011, that:

Of the 472 civilian occupations, only six are majority immigrant (legal and illegal). These six occupations account for 1 percent of the total U.S. workforce. Moreover, native-born Americans still comprise 46 percent of workers even in these occupations.

[Are There Really Jobs Americans Won’t Do?]

That's pretty similar to the following claim from three authors at Pew this spring:

Compared with their 5% share of the civilian workforce overall, unauthorized immigrants are overrepresented in farming and construction occupations (26% and 15%, respectively). In all industries and occupations, though, they are outnumbered by U.S.-born workers.

[5 facts about illegal immigration in the U.S., by Jens Manuel Krogstad, Jeffrey S. Passel, and D'Vera Cohn, April 27, 2017]

The two statements differ slightly because Pew's is restricted to illegal aliens, while CIS's also includes aliens here legally (i.e. lawful permanent residents and "temporary" workers).

Anyway, when discussing illegal immigration with your generally-clueless fellow citizens, you can assure them, "There are no jobs that American citizens won't do," and cite Pew as your authority.