-```
- GenomeDir:
- type: Directory
- inputBinding:
- prefix: "--genomeDir"
-```
-{: .language-yaml }
-
-Sometimes we want to provide input values to a step without making
-them as workflow-level inputs. We can do this with `{default: N}`.
-For example:
+> ## Exercise
+>
+> Look at `STAR-Align.cwl` and identify the input parameters that
+> correspond to the command line arguments used in the source script:
+> `--runThreadN`, `--genomeDir`, `--outSAMtype`, and
+> `--outSAMunmapped`. Also identify the name of the output parameter.
+> Use these to write the STAR step.
+>
+> > ## Solution
+> >
+> > input parameter name: RunThreadN, GenomeDir, ForwardReads, OutSAMtype, SortedByCoordinate, OutSAMunmapped
+> >
+> > output parameter name: alignment
+> {: .solution}
+{: .challenge}