add warning to readme (#2568)

* make warning prominent

* make warning prominent

docs/new_task_guide.md

@@ -190,7 +190,8 @@ doc_to_target: "{{answer}}"
 ```
 
 
-**Important**: we now add `target_delimiter` between input and target which defaults to " ", such that the full input-output string is `doc_to_target(doc) + target_delimiter + doc_to_text(doc)`. `doc_to_text` and `doc_to_target` should not contain trailing right or left whitespace, respectively.
+> [!WARNING]
+> We add `target_delimiter` between input and target which defaults to " ", such that the full input-output string is `doc_to_text(doc) + target_delimiter + doc_to_target(doc)`. `doc_to_text` and `doc_to_target` should not contain trailing right or left whitespace, respectively. For multiple choice the target will be each choice index concatenated with the delimiter.
 
 
 #### Multiple choice format
@@ -206,7 +207,7 @@ doc_to_choice: "{{[distractor1, distractor2, distractor3, correct_answer]}}"
 ```
 Task implementers are thus able to decide what the answer choices should be for a document, and what prompt format to use.
 
-The label index can also be sourced from a feature directly. For example in `superglue/boolq`, the label index if defined in the feature `label`. We can set `doc_to_target` as simply `label`. The options or verbalizers can be written in a the form of a list `["no", "yes"]` that will correspond to the label index.
+The label index can also be sourced from a feature directly. For example in `superglue/boolq`, the label index if defined in the feature `label`. We can set `doc_to_target` as simply `label`. The options or verbalizers can be written in the form of a list `["no", "yes"]` that will correspond to the label index.
 
 ```yaml
 doc_to_text: "{{passage}}\nQuestion: {{question}}?\nAnswer:"