1. **Problem statement:** We are given a parallelogram KGHJ with angle $\angle K = 38^\circ$. We need to find the size of angle $\angle KGH$.
2. **Recall properties of parallelograms:**
- Opposite sides are parallel and equal in length.
- Opposite angles are equal.
- Adjacent angles are supplementary (sum to $180^\circ$).
- Consecutive interior angles between parallel lines are supplementary.
3. **Identify angles:**
- Since $KG \parallel HJ$ and $KH \parallel GJ$, $KGH$ is a parallelogram.
- Given $\angle K = 38^\circ$, the angle adjacent to $\angle K$ along side $KG$ is $\angle G$.
4. **Calculate $\angle G$:**
- Adjacent angles in a parallelogram sum to $180^\circ$.
- So, $\angle K + \angle G = 180^\circ$.
- Substitute $\angle K = 38^\circ$:
$$\angle G = 180^\circ - 38^\circ = 142^\circ$$
5. **Conclusion:**
- The size of angle $\angle KGH$ is $142^\circ$.
**Final answer:**
$$\boxed{142^\circ}$$
Angle Kgh 7D706F
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